(HealthNewsDigest.com) - One-third of women at risk of unintended pregnancy used withdrawal as a contraceptive method within the past 30 days, often in combination or rotation with more effective methods, according to "Pull and Pray or Extra Protection? Contraceptive Strategies Involving Withdrawal AmongU.S. Adult Women," by Rachel K. Jones of the Guttmacher Institute et al. The new study, which is currently available online and will appear in a forthcoming issue ofContraception, also found that 13% of women surveyed reported that withdrawal was the most effective contraceptive method they had used in the last 30 days, while 15% reported that the most effective method used was a long-acting reversible method, 21% condoms and 35% the pill.

The study analyzed national data from 3,276 women aged 18-39 in 2012. It found that among the one-third of women who had used withdrawal in the last 30 days, 12% reported using only withdrawal; the majority of women who practiced withdrawal also used a hormonal method (13%) or condoms (11%) within that time frame.

Women aged 18-24 also were the most likely to have used withdrawal at least once in the last 30 days, and reliance on withdrawal generally decreased as women's age increased. Moreover, younger women were especially likely to use withdrawal in combination or rotation with more effective methods such as IUDs, the injectable, patches and rings, or with condoms. Although 41% of 18-24-year-olds had used withdrawal at least once in the last 30 days, just 10% relied only on this method. Women in dating relationships and those strongly motivated to avoid pregnancy also had some of the highest levels of combining withdrawal use with condoms or highly effective methods.

"Some couples who use withdrawal may be more vigilant about preventing pregnancy than those who do not," said Dr. Jones, the study's lead author. "These users might be choosing to ‘double up' because they perceive the consequences of unintended pregnancy to be especially dire for them."

Since substantial minorities of couples are using withdrawal, the authors recommend that providers discuss both the pros and cons of the method with patients. They note that while withdrawal is only slightly less effective than condoms at preventing pregnancy, providers should emphasize that the method does not protect against STIs.